Imitation-Inhibition Task¶
HED Task ID: hedtsk_imitation_inhibition
Also known as: Automatic Imitation Task, Automatic Imitation, Brass Imitation Task, Stimulus-Response Compatibility Imitation Task, Action Observation Compatibility Task
Execute an instructed finger movement while observing a congruent or incongruent action performed by another person; the congruency effect (faster responses on congruent trials) indexes automatic imitation and the cost of inhibiting observed-action representations.
Description¶
The Imitation-Inhibition Task (Brass, Bekkering, Wohlschlager, & Prinz, 2000) measures the involuntary tendency to copy observed actions and the executive cost of suppressing that tendency. Participants are cued to perform a simple action (e.g., lift the index finger when a number ‘1’ appears) while simultaneously viewing a task-irrelevant video of another person’s hand performing either the same action (congruent), a different action (incongruent, e.g., lifting the middle finger), or no action (neutral/static hand). The congruency effect – faster and more accurate responses on congruent than incongruent trials – indexes automatic imitation, while the interference effect (incongruent minus neutral) specifically indexes the inhibitory cost of suppressing the observed action. The paradigm is grounded in common-coding / ideomotor theory (Prinz, 1997): perceiving an action activates the same motor representations as executing it, creating response conflict when the observed and instructed actions differ. The task has become a standard probe of the human mirror system and self-other distinction. The automatic imitation effect is modulated by animacy (stronger for human than robotic agents), social context (in-group vs. out-group models), empathy, and developmental stage (weaker in young children, inverted-U trajectory). Clinical applications include autism spectrum conditions (mixed findings on reduced automatic imitation) and schizophrenia (impaired self-other distinction).
Inclusion test¶
Procedure |
Participants perform an instructed action (e.g., finger lift) in response to a symbolic cue while simultaneously observing a task-irrelevant video or animation of another agent performing a congruent, incongruent, or neutral action. |
Manipulation |
Congruency (observed action matches vs. mismatches instructed action); agent type (human hand, robotic hand, non-biological stimulus); social context (in-group vs. out-group model); action type (finger lift, hand open/close, whole-arm movement); spatial compatibility control (orthogonal spatial arrangement to dissociate imitative from spatial compatibility). |
Measurement |
Congruency effect (RT and error rate difference: incongruent minus congruent); interference effect (incongruent minus neutral); facilitation effect (neutral minus congruent); congruency effect magnitude as individual-difference measure; EEG mu-suppression as neural index of motor simulation. |
Variations¶
Variation |
Description |
Justification |
|---|---|---|
Classic Finger-Lift Paradigm (Brass et al.) |
Lift index or middle finger in response to a number cue while observing congruent or incongruent finger lifts. The foundational paradigm. Includes spatial compatibility controls. |
Canonical: respond to number cue, observe incongruent finger lift |
Kinematic Paradigm (Kilner Task) |
Participants move their arm (e.g., horizontally) while watching a model move horizontally or vertically. Automatic imitation measured by increased trajectory variance when the model’s movement is incompatible. Continuous rather than discrete measure. |
Perform arm movement while observing congruent/incongruent arm; different motor effector |
Hand Open/Close Variant |
Open or close the hand in response to a cue while observing congruent or incongruent hand movements. Larger effector; may engage different motor representations than finger movements. |
Open/close hand in response to/despite observed hand action |
Animacy Manipulation |
Compare automatic imitation of human hand, robotic hand, and non-biological (e.g., geometric) stimuli. Tests whether the mirror system is preferentially tuned to biological agents. |
Animate vs. inanimate observed movement; tests social specificity of imitation |
Goal-Directed Imitation Variant |
Observe a model grasping an object; measure whether automatic imitation is driven by the movement kinematics or the action goal. Dissociates kinematic and goal-level motor representations. |
Imitate goal vs. means; tests level of imitative representation |
Vocal Stimulus-Response Compatibility |
Hear a speech sound (e.g., ‘pa’) while producing a different sound (e.g., ‘ba’). Vocal analogue of the manual imitation-inhibition task. Tests automatic imitation in the speech domain. |
Vocal response to observed action; different response modality |
Controlled Imitation Task (Reverse) |
Participants are cued to act but must mimic the observed action on a subset of trials. Reverses the standard task demands: measures the ability to prioritize imitation over instructed action. |
Instructed to imitate or not; tests explicit voluntary control |
Counter-Imitation Training |
Heyes et al. sensorimotor learning paradigm: train incompatible associations (see index lift, execute middle lift) to test whether automatic imitation is learned or innate. Automatic imitation is abolished or reversed after training, supporting associative sequence learning accounts. |
Training to suppress imitation; tests plasticity of imitative tendencies |
Cognitive processes¶
This task engages the following cognitive processes:
Key references¶
{‘authors’: ‘Brass, M., Bekkering, H., Wohlschläger, A., & Prinz, W.’, ‘year’: 2000, ‘title’: ‘Compatibility between Observed and Executed Finger Movements: Comparing Symbolic, Spatial, and Imitative Cues’, ‘venue’: ‘Brain and Cognition’, ‘venue_type’: ‘journal’, ‘journal’: ‘Brain and Cognition’, ‘volume’: ‘44’, ‘issue’: ‘2’, ‘pages’: ‘124-143’, ‘doi’: ‘10.1006/brcg.2000.1225’, ‘openalex_id’: None, ‘pmid’: None, ‘citation_string’: ‘Brass, M., Bekkering, H., Wohlschlager, A., & Prinz, W. (2000). Compatibility between observed and executed finger movements: Comparing symbolic, spatial, and imitative cues. Brain and Cognition, 44(2), 124-143.’, ‘url’: ‘https://doi.org/10.1006/brcg.2000.1225’, ‘source’: ‘crossref’, ‘confidence’: ‘high’, ‘verified_on’: ‘2026-04-20’}
{‘authors’: ‘Heyes, C.’, ‘year’: 2011, ‘title’: ‘Automatic imitation.’, ‘venue’: ‘Psychological Bulletin’, ‘venue_type’: ‘journal’, ‘journal’: ‘Psychological Bulletin’, ‘volume’: ‘137’, ‘issue’: ‘3’, ‘pages’: ‘463-483’, ‘doi’: ‘10.1037/a0022288’, ‘openalex_id’: None, ‘pmid’: None, ‘citation_string’: ‘Heyes, C. (2011). Automatic imitation. Psychological Bulletin, 137(3), 463-483.’, ‘url’: ‘https://doi.org/10.1037/a0022288’, ‘source’: ‘crossref’, ‘confidence’: ‘high’, ‘verified_on’: ‘2026-04-20’}
Recent references¶
{‘authors’: ‘Cracco, E., Bardi, L., Desmet, C., Genschow, O., Rigoni, D., De Coster, L., Radkova, I., Deschrijver, E., & Brass, M.’, ‘year’: 2018, ‘title’: ‘Automatic imitation: A meta-analysis.’, ‘venue’: ‘Psychological Bulletin’, ‘venue_type’: ‘journal’, ‘journal’: ‘Psychological Bulletin’, ‘volume’: ‘144’, ‘issue’: ‘5’, ‘pages’: ‘453-500’, ‘doi’: ‘10.1037/bul0000143’, ‘openalex_id’: None, ‘pmid’: None, ‘citation_string’: ‘Cracco, E., Bardi, L., Desmet, C., Genschow, O., Rigoni, D., De Coster, L., Radkova, I., Deschrijver, E., & Brass, M. (2018). Automatic imitation: A meta-analysis. Psychological Bulletin, 144(5), 453-500.’, ‘url’: ‘https://doi.org/10.1037/bul0000143’, ‘source’: ‘crossref’, ‘confidence’: ‘high’, ‘verified_on’: ‘2026-04-20’}
{‘authors’: ‘Genschow, O., van Den Bossche, S., Cracco, E., Bardi, L., Rigoni, D., & Brass, M.’, ‘year’: 2017, ‘title’: ‘Mimicry and automatic imitation are not correlated’, ‘venue’: ‘PLOS ONE’, ‘venue_type’: ‘journal’, ‘journal’: ‘PLOS ONE’, ‘volume’: ‘12’, ‘issue’: ‘9’, ‘pages’: ‘e0183784’, ‘doi’: ‘10.1371/journal.pone.0183784’, ‘openalex_id’: None, ‘pmid’: None, ‘citation_string’: ‘Genschow, O., van Den Bossche, S., Cracco, E., & Brass, M. (2017). Mimicry and automatic imitation are not correlated. PLoS ONE, 12(9), e0183784.’, ‘url’: ‘https://doi.org/10.1371/journal.pone.0183784’, ‘source’: ‘crossref’, ‘confidence’: ‘high’, ‘verified_on’: ‘2026-04-20’}
{‘authors’: ‘De Coster, L., Wiersema, J. R., Deschrijver, E., & Brass, M.’, ‘year’: 2017, ‘title’: ‘The effect of being imitated on empathy for pain in adults with high-functioning autism: Disturbed self–other distinction leads to altered empathic responding’, ‘venue’: ‘Autism’, ‘venue_type’: ‘journal’, ‘journal’: ‘Autism’, ‘volume’: ‘22’, ‘issue’: ‘6’, ‘pages’: ‘712-727’, ‘doi’: ‘10.1177/1362361317701268’, ‘openalex_id’: None, ‘pmid’: None, ‘citation_string’: ‘Deschrijver, E., Wiersema, J. R., & Brass, M. (2017). Action-based touch observation in adults with high functioning autism. Social Cognitive and Affective Neuroscience, 12(2), 273-282.’, ‘url’: ‘https://doi.org/10.1177/1362361317701268’, ‘source’: ‘crossref’, ‘confidence’: ‘high’, ‘verified_on’: ‘2026-04-20’}
{‘authors’: ‘Kilner, J., Paulignan, Y., & Blakemore, S.’, ‘year’: 2003, ‘title’: ‘An Interference Effect of Observed Biological Movement on Action’, ‘venue’: ‘Current Biology’, ‘venue_type’: ‘journal’, ‘journal’: ‘Current Biology’, ‘volume’: ‘13’, ‘issue’: ‘6’, ‘pages’: ‘522-525’, ‘doi’: ‘10.1016/s0960-9822(03)00165-9’, ‘openalex_id’: None, ‘pmid’: None, ‘citation_string’: ‘Kilner, J. M., Paulignan, Y., & Blakemore, S. J. (2003). An interference effect of observed biological movement on action. Current Biology, 13(6), 522-525.’, ‘url’: ‘https://doi.org/10.1016/s0960-9822(03)00165-9’, ‘source’: ‘crossref’, ‘confidence’: ‘high’, ‘verified_on’: ‘2026-04-20’}